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Remove also the entire D:\XperienCentral\deploy\web folder.
Supporting Drag to Scroll in Firefox
In the XperienCentral Editor, if you use the web browsers Internet Explorer and Chrome, you can drag an item to the bottom of the window and the content scrolls up, which allows you to drag the item below the visible area. Firefox does not natively support this browser feature, however, an add-on is available from Mozilla that adds this functionality. If your XperienCentral users want to use this feature in Firefox, you can download and install the add-on from the following URL: https://addons.mozilla.org/en-US/firefox/addon/drag-to-scroll-reloaded/.